1. Field of the Invention
This invention pertains to the field of surgical appliances and specifically to appliances used in the reduction of bone fractures. It includes a cannula through which a drilling burr secured to one end of a flexible shaft may be guided to drill holes in bones and then used to guide a wire to reduce the fracture, such that the disruption of surrounding muscle tissue and amount of wire used is minimal and a guide apparatus which positions the cannula precisely for minimal damage to surrounding tissues. It also pertains in general to the field of binding and cutting pliers.
2. Description of the Prior Art
This invention is designed to solve a specific problem which occurs in the reduction of fractures when the bone is wired together on both sides of the fracture. Fractured bones are frequently wired together to prevent rotational movement of the pieces during the healing process and to prevent distraction or separation of the fractured parts. In order to wire a fracture, an incision must be made in the area of the fracture, the soft tissue pulled away from the bone on both sides of the fracture and holes must be drilled through the cortex of the bone on each side of the fracture. Wire is then inserted through one hole, pulled through the medula and then out the other hole where it is tied. The problem with this procedure is that too much soft tissue is pulled away from the bone and damaged, and the blood supply to the bone is impaired. The instrument of the present invention is specifically designed to minimize the amount of soft tissue which needs to be separated from the bone and thereby insure an adequate supply of blood to the fractured parts. Further advantages include less trauma to the fracture site, less chance of post-operative infection and more rapid healing.
A search of the prior art reveals many patents in the field of wire binding and cutting pliers of a scissor or plier type such as those disclosed in U.S. Pat. Nos. 914,182; 1,304,620 and 1,641,077. There are also many prior patents on bone clamps, some of which use pins or wires and some of which are drill guides. Examples are U.S. Pat. Nos. 2,291,413; 2,834,342; 2,181,746; 2,583,896 and 2,455,609. None of these devices performs the same function as that of the present invention. Each has some problems associated with it which may not be obvious to the layman. For example, U.S. Pat. No. 2,455,609 teaches a wire applying forceps which initiates and adjusts a line loop to a desired completion. The device of this patent, which is commercially available, wraps a wire around (not through) a bone and a tight wire around a bone can cut off blood circulation to the bone. Other known devices have similar drawbacks.
The inventor knows of no surgical instrument which performs the functions of the device of this invention.